This invention is generally concerned with apparatus for opening envelopes and more particularly with the provision of means for bending the body portion of an envelope against a guide member for forming a gap between the flap and body portions of the envelope.
In high speed envelope feeding machines which are constructed and arranged for opening envelopes as a preparatory step to further processing, such as stuffing, moistening and sealing, there has been a long felt need for simplified structure for performing the function of opening the flap portions of the envelopes while avoiding jamming them against the opening structure. Various attempts to provide such structures are shown in U.S. Pat. Nos.: U.S. Pat. No. 2,028,277 for an Envelope Flap Opening and Moistening Device, issued Jan. 21, 1936 to Finfrock; U.S. Pat. No. 3,474,711 for a Envelope Flap Deflecting Apparatus, issued Oct. 28, 1969, to Swinyar; U.S. Pat. No. 3,747,297 for a Flap-Opening Apparatus, issued July 24, 1973, to Hankins; U.S. Pat. No. 3,910,007 for a Device For Opening the Flaps of Envelopes, issued Oct. 7, 1975 to Dorer; U.S. Pat. No. 3,935,800 for a Flap Separating Mechanism issued Feb. 3, 1976 to Sette, et al; U.S. Pat. No. 3,974,749 for Envelope Flap Separating and Distending Method and Mechanism, issued Aug. 17, 1976 to Luperti, et al; U.S. Pat. No. 3,996,727 for an Envelope Flap Separating Mechanism, issued Dec. 14, 1976 to Irvine, et al; U.S. Pat. No. 4,715,164 for a High Speed Envelope Flap Opening, issued Dec. 29, 1987 to Luperti, et al; U.S. Pat. No. 4,813,209 for a Single Cycle Envelope Flap Opener, issued Mar. 21, 1989 to Foster, et al; and U.S. Pat. No. 4,846,455 for High Speed Envelope Feeding Apparatus, issued July 11, 1989 to Hurst.
Although the structures shown and described in the above listed U.S. Patents perform the envelope opening function, when envelope feed speeds are accelerated to speeds of up to four envelopes per second, machine down times occasioned by envelope jams and misses occur with increasing frequency, due to minor functional problems inherent in the various envelope opening structures becoming magnified, and due to having to reconsider the magnitude of the forces exerted on rapidly moving envelopes to achieve desirable, while avoiding undesirable, envelope distortion effects arising from the differences between the physical characteristics of rapidly versus slowly moving envelopes.
Accordingly:
An object of the invention is to provide simplified apparatus for opening an envelope; and
Another object is to provide envelope opening apparatus including a rotatable finger member which engages the flap portion folded over the body portion of an unsealed envelope and bends the body portion thereof against a guide to form a gap between the flap and body portions.